5693 as a phono preamp?

[Burnedfingers]

Just wondering if someone has had experience using a 5693/6SJ7 as a phono preamp. If so do you have any schematics to share?

Thanks

 

[SY]

Triode connected?

 

[Burnedfingers]

Well, it only has an amplification factor of 19 when it is triode connected. I cannot find the amplification factor in pentode. Maybe its not a good choice after all.

 

[SY]

Pentodes in general aren't good phono stage tubes because of partition noise, the excess noise inherent in pentodes because of the statistical nature of electron flow when given a choice between screen and plate. In this service, you'd do better with a triode. The 5691 could be a good choice if you can live with the input capacitance (a few hundred pF).